Elevator-brake mechanism



E. B. THURSTON ELEVATOR BRAKE MECHANISM Filed June 27, 1819 2Sheets-Sheet 1 an Mum I MM April 22 1924.

- 1,491,442 E. B. THURSTON ELEVATOR BRAKE MECHANISM Filed June 27. 19192 Sheets-5heet 2 gnvawtom Patented Apr. 22, 1924.

, UNITED sures PATENT Mme.

ERNEST B. 'rnuns'ron, or TOLEDO, c1110, "Ass'ronon To run nnuen ronELEVATOR a MACHINE 00., or TOLEDO, 01110, aconrona'rron or 01110.

ntnvsronnnrmxn MEcHAmsn.

Application filed June 27, 1919. Serial No. 307,246.

To all whom it may c ncern: 1

Be it known thatLERNEs'r B. Tnuns'ron, a citizen of the United States ofAmerica, residing at Toledo, Lucas County, Oh o, 'have invented new anduseful Elevator Brake Mechanisms, of which .the following is. aspecification.

This invention relates to control of a power actuated member,articularly for the stopping thereof gradua ly in approaching or findinga definite position. 1 This invention has utility in givingflexibilityin unskilled handling of alternating current elevators. I

. Referring to the drawingsa Fig. 1 is a wiring diagramof an embodimentof the invention as a double setting brake 'in. an alternating electriccurrent elevator installation; I

Fi 2 is a wiring diagram of an elevator installation in which thecontroller coacts directly in one of the multiple brake settings,instead of through adirection switch; and

Fig. 3is a wiring dia am of an elevator installationsimilar to t eshowing of Fig. 1, without the interlocking features.

Elevator car 1 is shown as having therein a controller 2 formain switch3 and direction switches 4, 5,;for cutting off and supplying power tomotor 6 and thereby driv ing or stopping shaft 7 as a drivenmember fromthe motor 6 for actuating the elevator 1. I

The controller 2 has a contact8 of an extent to span an adjacent threeof contacts 9, 10, 11, 12, 13, 14. At central or off position,thecontact 8 is on the contacts 11, 12, connected to each other and by linecon- 40 nected to power line '16 extending to terminal-17 at the mainswitch 3. In shifting "the controller 2 for downward travel, terminal.or contact 8 is first rocked to connect contacts 12, 13. Contacts 10,'13, are con- 45 nectedand by line 18 are placed in a circuitpast'bottomlimit switch 19, with line 20, past top limit switch 21, withlines 22, 23, past switch 24, with line through main switch energizingcoil 26 to power supply 50 line 27. With the switch 24 closed, thisfirst position of the controller 2 may close the main switch 3,andthrough lines 28, 29, therefrom electromagnetic brake coil 30 may beenergized to free or releasebrake drum 31 and thus effect a partialrelease of the holding means for the shaft 7.. Under many circumstancesitis desirable that on starting, the release of the shaft 7 be acomplete freeing thereof on the instant of the starting of the motor 6.For such a mode of operation, the switch 24 is opened, and themain'switch throwing position with the contact 8 on the contacts 11,12,13, is not effective for the throwing of the switch 3. The furthermovement to the position placing the contact 8 onthe contacts 12, 13,14, not only operates the direction switch 5 for down direction travel,but also through an interlock permits simultaneous energ1z ing of themain switch 3. From the contact 14 by way of line 32,- lower limitswitch 33, line 34, down direction switch coil 35, and line 36 to powersupply line 27 there may current flow through the contacts 8, 12, andthe line .15 to power supply line 16, thus throwingdown directionsswitch 5. brings contact 37 to close circuit fromthe 'line 34, throughcontacts 38, 39, to line 40 extending to the coil 26 of the main switch3 and thence to power supply line 27. The main switch 3 is thusenergized to operate interlock contact 41 to close circuit from the line40, through terminals 42, 43, and line 44 to the line 22, as aninterlock by-pass as to the switch 24 to the controller contact 13. Theswitch 3 may now be kept energized even if the controller 2 be rocked tomove the contact 8 off the contact 14 de-energizing direction switch 5thus cutting off power from lines 27, 45, to the motor 6, by way oflines 46, 47. Single power line 48 from the main switch 3 and power line16, thus may not complete a circuit in the three phase alternatingelectric current system, and the motor 6 has no driving energy.

Connected at terminal 49 with the power line 46 from the down directionswitch 5,-

is a line 50 extending to electroma etic brake coil 51, the circuitthrough which is completed by a line 52 extending to terminal 53connected with the power line 47 from the down direction switch 5. Thismeans that when the down direction switch 5 is thrown to start the motor6,'there is a freeing of the shaft 7 not only at the brake drum 54 bythe energizing of the coil 51, but as the This switch 3 issimultaneously thrown, the drum 31 is also freed by the coil 30 beingenergized. Accordingly at the instant of direction throw position beingattained by the 5 controller 2 in the elevator 1, the two settings ofthe holding means at the brake drums 31 and 54, are released, and themotor 6 at once actuates the shaft 7 in the direction to cause theelevator car 1 to deseend.

' resultin in a cuttin ofi of ower su l to the motor 6, andsimultaneously a partial setting of the holding means, for the openingof the switch 5 de-energizes the brake coil 51, resulting in a brakeholding action 39 upon the drum 54-. This feature has exceptionaladvantages in the handling of cars with different loads, in makingpossible and practical simple see-sawing or coasting to eifect anaccurate landing or floor stop, so

essential in wheeling in and out heavy loads,

as well as for the safety of passengers against stub-toe accidents. Thisbrake drum 54 in its holding may act as a normal stopping brake, but inreality allow some slip- 39 page. Should such slippage not bring the carto the accurate stop desired, the controller 2 may be rocked in forstarting the motor 6. This rocking may be very quickly performed with areturn to cut out position for the motor 6 almost before the motor canpick up. however, the brake drum 54 was released, and there is thus carfreedom for the slight inching or creeping to a floor level. Once thfloor level is reached, the controller 2 is swung to move the contact 8off the contact 13, and the emergency of complete holding action iseffective in the second setting of the holding means by deenergizing thecoil 30 and gripping of the brake drum 31.

The relation of the effective holding of th two settin s of the brakeholding means may be such tnat the stopping setting is just suiiicientto handle the traveling car to bring it to a stop, while the secondsetting may be a sufiicient addition thereto in so holding that theremaybe no settling of the car upon loading, or shifting of the car uponunloading-a feature of considerable advantage in keeping the car at alanding in precluding ccidents. lVith these interlocks on the mainswitch as controlled from the direction switch, should the operatorshift the con troller 2 to move the contact 8 clear not only of contact14, but also of the contact 13, there may be no release of either braksetting until the controller 2 has been shifted to a running position.When both settings have been freed, there may be a removal and replacingof one setting, with consequent flexibility in control. Once there hasbeen a full setting, such may not be disturbed except by bringing thecontroller into running position, say for an up movement, has the fullascent not been attained, or for a down movement, if the up traveldistance has been exceeded.

In this former event, the controller is shifted to bring the contact 8across the contacts 9, 10, 11. The contact 9 is the direction controlanalogous to the contact 14, but extends by line past upper limit switch56, thence by line 57 to up direction switch coil 58 to the line 36 andthe power line 27. The switch 4 is thus closed for operating the motor 6for upward direction travel of the car 1. This closing of the switch 4,is identical with the action of the switch 5 in releasing the brakesetting at the drum 54. Likewise, at once the switch 4 is opened, thecoil 51 is tie-energized, and this setting of the holding means iseffective independent of the holding action of the drum 31, if thecont-roller 2 have its contact 8 on either contact 10 or 13.

lVhen the switch 24 is closed the holding means settings may be steppedin release as well as in applying, but under heavy load conditions,there may be preference in avoiding any partial release of the car withthe drive not taking hold, so especially in the extreme conditions,safety precautions may dictate keeping the switch 24 open. It is truewith this switch 24 open, there may be greater ease in releasing the car1, and possibly greater speed in making landings where the operator isdisposed to give the controller 2 full swing to center, or past center,instead of just clear of a direction contact 14, or 9. In the instanceof a swing past central or off position, which brings the contact 8 fromcontact 13 to contact 10, the break occurs at contact 14 or 9, with theswitch 24 open, and to again gain control of the release for the brakemeans, the controller 2 must be swung to a direction contact 14 or 9.

In upward travel, should the operator neglect to shift the controller 2to oil or central position, and the elevator 1 then move to open theupper limit switches 21, 56, the two brake settings are simultaneouslyapplied, and no controller manipulation may be had for further uptravel. The controller 2 must be brought to olf position and then swungto down direction, when the two settings are automatically electricallyreleased as the car 1 descends. This is an insurance against anexcitable operator doing the wrong thing in an emergency. Identicaloperation precludes exceeding the down travel limit, for the elevator inopening limit switches 19, 33, at once causes the holding means to beapplied to the drums 54, 31, simultaneously, and the car may only bestarted by shifting thecontroller 2 for direction travel.

the car lleaves the region of the limitswitches they may beautomatically reset;

Like the switch 5 and its interlock 37, the

up switch 4, has interlock contact 59 con .nectin the line .57 throughterminals 60,

61, wit the line 410v for energizing the main switch coil 26. I

From the power supply line 27, current past the main switch 3 may passby way of line 62 to the direction switches at, 5.

The multiple brake setting feature in I i Fig. 2 is shown as having oneof the setthe motor 6..

1 tin an the mainswitch 3. The coils 30, 51,

thereof in series with the controller 2 are here shown as in seriesduringthepartial setting stage. The controller-2 is provided with acentral magnetic core section 63, which in the oscillation ofthecontroller 2 away from off or central position, may respectively moveout offixed coil connected by the line 28to the main switch 3.

Line 66 extending from the coil 65 connects to the coil 51 and by way ofthe coil 30 to line 29 and the main switch 3. The reactance at the coil65 is reduced by moving the core 63 out of thecoil 65' and the currentthrough the two electromagnet coils 51, 30, in series, effects a partialfreeing of the holding or brake means for the shaft 7 of A furthershiftingv of the controller 2 to a direction switch position, at oncecauses the lines 50, 52, to energize relay coil 67 throwing contact68 toconnect the third phase of the power line 45 through terminals 69, 70,and line 71, with the brake releasing coils 30', 51, between suchcoils., Instead of I single phase freeing, there is now three phasecurrent action as a second stren th release in fully freeing the shaft 7for tie selected direction of elevator car actuation. Whenever thecontroller 2 is shifted from a direction contact 14 or9, the'coil 67 isdeenergized, the relay 68 is opened, and the two brake coils 51, 30,lapse from three phase or intermediate neutral leg polyphase control, tosingle phase series action. The

brake setting spring means are thus permitted to be partially effectivewhile the. n'iot-or 6 has its power cutoff, and there is the furtherflexibility of control in working the car to the desired definiteposition of A simplified embodiment of the double setting brake withmain and direction With the elevator car under way, some sliding orinching along may be had withslight loss of time, in quickly bringingthe car accurately to a landing. As the land-' ing is reached, athrow ofthe controller 2 to central or off position, at once applies the mainswitch controlled or emergency brake by releasing the shoes controlledby the coil 30, or completing the brake setting. When the controller 2is in main-switch throwing position in shifting therefrom to a contact10 or 13, a partial freeing of the holding means occurs. As thecontroller in further movement comes to a running position upondirection contact 9 or 14, full freeing of the driven member 7 is hadsimultaneous with the pick-up action of the motor 6. In bringing the carto a stop, the coil 51 may be de-energized to permit action of thestopping brake, and there may be see-sawing, or coasting in throwingthis brake in and out, in feeling the car to a desired landing. The offposition of the controller 2, then permits application of both brakesettings. Then these two settings approximate equality final holding isadequate for holding the car under any normal and even abnormal. loadingand unloading conditions. This positive holding is always effective withthe controller in off position, yet in usual opera-- tion there maybe amost smooth handling of the car to a stop, due to the modified or lesserholding action of but one setting. This is a feature of utility, notonly as to comfort for passengers, but as greatly contributing to thelife of the installation in that extreme shocks in stopping are readilyavoided. In Fig. 3 the main switch control lines extend separatelythrough the limit switches.

What is claimed and it is desired to secure by Letters Patent is:

1. An elevator, electric driving means therefor including a motor, mainand direction switches for the motor, a single controller for theswitches having an off cen tral position and on each side thereof a mainswitch throwing position and then an additional direction switchthrowing position, connecting means between the respective directionswitches and the respective directions switch positions at thecontroller effective in off position of the controller as to a directionposition to render the driving thercbetween, the

-- the respective directions switch positions at the controllereiiective in on position of the controller as to direction position torender the drivin means inoper tive, brake means for the elevator, andconnections for operating the brake means by shifting the controllerfrom a main switch position to olt position.

3. An elevator, electric driving means therefor including a motor, mainand direction switches for the motor, a single controller for theswitches having a central oft position and on each side thereof a. mainswitch throwing position and then therebeyond an additional directionswitch throwing position, connecting means between the respectivedirection switches and the respective directions switch positions at thecontroller ei'iective in oil' position of the cont-roller as to adirection position to render the driving means inoperative, doublesetting brake means for the elevator, and connections for operating thebrake means by shitting the controller from a. direction switch throwingposition to a main switch throwing position to effect one setting of thebrake means and in additional movement to oil position to eii'ect asecond setting of the brake means.

4. An elevator, electric driving means therefor including a motor, mainand direction switches tor the motor, a single controller tor theswitches having a central off position and on each side thereof a mainswitch throwing position and there beyond an additional direction switchthrowing position, connecting means between the respective directionswitches and the respective directions switch positions at thecontroller ei'iective in oii" position oi the controller as to adirection position to render the driving means inoperative, doublesetting brake means for the elevator, connections for operating thebrake means by shifting the controller different distances, andinterlocking means additionally providing for simultaneous release ofthe two settings of the brake means.

5. An elevator, electric driving means therefor including a motor, mainand direc tion switches for the motor, a controller for the switcheshaving a central oil position and on each side thereof a main switchthrowing position and therebeyond a direction switch throwing position,multiple setting bralze means for the elevator operable in shifting thecontroller, to dill'erent positions in a common direction in effectingseparate settings for holding the elevator through the brake means andin the reverse direct-ion effecting a release of one settingsimultaneous with the release of another setting of the means.

6. An elevator, limit switch means therefor, polyphase brake means forthe elevator means for effecting setting of the brake in one phase andmore than one phase. and control connections from the switch means tothe brake means for simultaneously oper ating the settings of the brakemeans to hold the elevator.

7. An elevator, an alternating electric current motor for driving theelevator, main and direction switches for the motor, a, controlleroperable from the elevator for actuating said switches; electricallycontrolled holding means having a plurality of settings for releasingand holding the elevator, connections from the controller for effectingac cording to the position of the controller different settings of theholding means; and upper and lower limit switches provided withconnections to the holding means permitting release by the controller ofa holding means setting from simultaneous full setting by a limit switchonly by reversal of the controller for changing the direction ofelevator travel, said single controller by such reverse operationbringing the elevator into controllable travel away from said limitswitch which may be closed by elevator travel theretoward.

8. An elevator, a motor for driving the elevator, a controller for themotor operable from the elevator, electrically controlled holding meanshaving a plurality of settings for releasing and holding the elevator,connections from the cont-roller for cllccting according to the positionof the controller difierent settings of the holding means, and a limitswitch connected to the holding means to permit release by thecontroller of a holding means setting from full setting by limit switchoperation only by reversal of the controller for changing the directionof elevator travel, said single controller by such reverse operationbringing the elevator into controllable travel away from said limitswitch which may be closed by elevator travel theretoward.

9. An elevator, a motor for driving the elevator, a controller for themotor operable from the elevator, multiple-settingelectrically-controlled holding means for releasing and holdin theelevator, connections from the control er for effecting differentsettings ofthe holdin means atdifierent positions of the control er, andlimit switches connected to the holding means to permit the con trollerto effect the releaseof the holding means only by controller movementtobring the elevator into reverse running from that which actuated thelimit switch( 10. An elevator a motor for driving the elevator, acontroller for the motor 0 erable from the elevator, poly hase electricaly controlled holding means aving a luralit-y of settings for releasingand holding the ele-' vator, connections from the controller forefl'ecting one setting of theholding'means in one phase and anothersetting of the holdingmeans in an additionalphase and a limit switchconnected to the holding means to preclude release of a holding meanssetting from full setting by limit switch operation except by reversalof the controller for changing the direction of elevator travel. 11. Anelevator, a motor for driving the elevator, a controllerfor the motoroperable from the elevator, a polyphase electric brake for the elevatorhaving a plurality of settings for releasing and holding the elevator,an connections from the controller for effecting one setting of theholding means in one phase and another setting of the holding means inan additional phase.

In witness whereof I affix my signature. ERNEST B. THURSTON.

